Interfacial heat transfer characteristics and thermal expansion behavior of heterostructure materials in arc-heated wind tunnel

Abstract

Structural ceramics such as carbon fiber reinforced silicon carbide (C/SiC) are of great importance for supersonic aircraft, where thermal-mechanical coupling behavior of materials affects the service performance of structural ceramics. In order to advance the understanding of the high temperature thermal-mechanical coupling behavior of heterostructure materials (one typical type of structural ceramics), we adopted here an optical observation system to visualize the variation of the gap width between heterostructure materials in arc-heated wind tunnel test. The variation of the gap width (decreasing and then volatility increasing) was observed during the test. Numerical simulation shows that thermal conduction and thermal expansion between the substrate and specimens play a critical role in the evolution of the gap width, as evidenced by the experiments. Additionally, the variation of the gap width under various conditions was given and a one-dimensional unsteady thermodynamic model of double-layer plate was established to reveal the gap evolution mechanism of heterostructure materials. The results of theoretical model agree well with numerical simulation.